Over the years, manufacturers have continued to add versatility to the control of implements attached to various machines. For instance, dozer blades attached to track type tractors originally only had control over lifting and lowering the blade. With time, additional control over tilting the blade about a fore-aft axis, angling the blade about an up-down axis, and pitching the blade about a left-right axis are additional capabilities that have been added to machines. In many such machines, the operator control station includes a conveyance control joystick on one side of the operator seat and an implement control joystick on the opposite side of the seat. The conveyance control joystick might be mounted on the left hand side and the implement control joystick mounted on the right hand side. In recent machines, the implement control joystick might be pivoted for and aft to lower and lift the blade, pivoted left and right to tilt the blade, and a thumb roller mounted on the joystick could be rotated to angle the blade. In the past, pitch control was generally accomplished by a turnbuckle mounted on the front of the machine, requiring the operator to stop the machine and manually rotate the turnbuckle in order to alter the pitch of the dozer blade. In more recent machines, a separate pitch cylinder might be mounted in place of a turnbuckle to control pitch, but a separate auxiliary valve of the hydraulic circuit was utilized to control pitch. For instance, pitch control might be plumbed into the hydraulic circuit by rerouting the hydraulic ports typically associated with the rear ripper to instead control the pitch cylinder. While utilizing the ripper hydraulic pathways to instead control pitch allowed the operator to control the dozer blade in four degrees of freedom without exiting the operator control station, control still required the operator to let go of the joystick and actuate the pitch control by a separate lever (ripper control lever) located in the operator control station.
Problems arise when there is a desire for the track type tractor to retain ripper hydraulic operation, but add blade pitch control without adding still another lever in the operator control station and providing hydraulic pathways to pitch control in a limited spatial envelope. The present disclosure is directed towards one or more of the problems set forth above.